// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_
#define CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_

#include <memory>

#include "base/strings/string16.h"
#include "build/build_config.h"
#include "content/common/content_export.h"
#include "third_party/WebKit/public/platform/WebInputEvent.h"
#include "third_party/skia/include/core/SkColor.h"
#include "ui/gfx/native_widget_types.h"

namespace gfx {
class Point;
class Rect;
class Size;
}

namespace ui {
class TextInputClient;
class AcceleratedWidgetMac;
}

namespace content {

class RenderWidgetHost;
class RenderWidgetHostViewFrameSubscriber;

// RenderWidgetHostView is an interface implemented by an object that acts as
// the "View" portion of a RenderWidgetHost. The RenderWidgetHost and its
// associated RenderProcessHost own the "Model" in this case which is the
// child renderer process. The View is responsible for receiving events from
// the surrounding environment and passing them to the RenderWidgetHost, and
// for actually displaying the content of the RenderWidgetHost when it
// changes.
//
// RenderWidgetHostView Class Hierarchy:
//   RenderWidgetHostView - Public interface.
//   RenderWidgetHostViewBase - Common implementation between platforms.
//   RenderWidgetHostViewAura, ... - Platform specific implementations.
class CONTENT_EXPORT RenderWidgetHostView {
public:
    virtual ~RenderWidgetHostView() { }

    // Initialize this object for use as a drawing area.  |parent_view| may be
    // left as nullptr on platforms where a parent view is not required to
    // initialize a child window.
    virtual void InitAsChild(gfx::NativeView parent_view) = 0;

    // Returns the associated RenderWidgetHost.
    virtual RenderWidgetHost* GetRenderWidgetHost() const = 0;

    // Tells the View to size itself to the specified size.
    virtual void SetSize(const gfx::Size& size) = 0;

    // Tells the View to size and move itself to the specified size and point in
    // screen space.
    virtual void SetBounds(const gfx::Rect& rect) = 0;

    // Retrieves the last known scroll position.
    virtual gfx::Vector2dF GetLastScrollOffset() const = 0;

    // Sets a flag that indicates if it is in virtual reality mode.
    virtual void SetIsInVR(bool is_in_vr) = 0;

    // Coordinate points received from a renderer process need to be transformed
    // to the top-level frame's coordinate space. For coordinates received from
    // the top-level frame's renderer this is a no-op as they are already
    // properly transformed; however, coordinates received from an out-of-process
    // iframe renderer process require transformation.
    virtual gfx::Point TransformPointToRootCoordSpace(
        const gfx::Point& point)
        = 0;

    // A floating point variant of the above. PointF values will be snapped to
    // integral points before transformation.
    virtual gfx::PointF TransformPointToRootCoordSpaceF(
        const gfx::PointF& point)
        = 0;

    // Retrieves the native view used to contain plugins and identify the
    // renderer in IPC messages.
    virtual gfx::NativeView GetNativeView() const = 0;
    virtual gfx::NativeViewAccessible GetNativeViewAccessible() = 0;

    // Returns a ui::TextInputClient to support text input or nullptr if this RWHV
    // doesn't support text input.
    // Note: Not all the platforms use ui::InputMethod and ui::TextInputClient for
    // text input.  Some platforms (Mac and Android for example) use their own
    // text input system.
    virtual ui::TextInputClient* GetTextInputClient() = 0;

    // Set focus to the associated View component.
    virtual void Focus() = 0;
    // Returns true if the View currently has the focus.
    virtual bool HasFocus() const = 0;
    // Returns true is the current display surface is available.
    virtual bool IsSurfaceAvailableForCopy() const = 0;

    // Shows/hides the view.  These must always be called together in pairs.
    // It is not legal to call Hide() multiple times in a row.
    virtual void Show() = 0;
    virtual void Hide() = 0;

    // Whether the view is showing.
    virtual bool IsShowing() = 0;

    // Indicates if the view is currently occluded (e.g, not visible because it's
    // covered up by other windows), and as a result the view's renderer may be
    // suspended. If Show() is called on a view then its state should be re-set to
    // being un-occluded (an explicit WasUnOccluded call will not be made for
    // that). These calls are not necessarily made in pairs.
    virtual void WasUnOccluded() = 0;
    virtual void WasOccluded() = 0;

    // Retrieve the bounds of the View, in screen coordinates.
    virtual gfx::Rect GetViewBounds() const = 0;

    // Returns true if the View's context menu is showing.
    virtual bool IsShowingContextMenu() const = 0;

    // Tells the View whether the context menu is showing.
    virtual void SetShowingContextMenu(bool showing) = 0;

    // Returns the currently selected text.
    virtual base::string16 GetSelectedText() = 0;

    // Subclasses should override this method to set the background color. |color|
    // could be transparent or opaque.
    virtual void SetBackgroundColor(SkColor color) = 0;
    // Convenience method to fill the background layer with the default color by
    // calling |SetBackgroundColor|.
    virtual SkColor background_color() = 0;
    virtual void SetBackgroundColorToDefault() = 0;
    virtual bool GetBackgroundOpaque() = 0;

    // Return value indicates whether the mouse is locked successfully or not.
    virtual bool LockMouse() = 0;
    virtual void UnlockMouse() = 0;
    // Returns true if the mouse pointer is currently locked.
    virtual bool IsMouseLocked() = 0;

    // Retrives the size of the viewport for the visible region. May be smaller
    // than the view size if a portion of the view is obstructed (e.g. by a
    // virtual keyboard).
    virtual gfx::Size GetVisibleViewportSize() const = 0;

    // Set insets for the visible region of the root window. Used to compute the
    // visible viewport.
    virtual void SetInsets(const gfx::Insets& insets) = 0;

    // Begin subscribing for presentation events and captured frames.
    // |subscriber| is now owned by this object, it will be called only on the
    // UI thread.
    virtual void BeginFrameSubscription(
        std::unique_ptr<RenderWidgetHostViewFrameSubscriber> subscriber)
        = 0;

    // End subscribing for frame presentation events. FrameSubscriber will be
    // deleted after this call.
    virtual void EndFrameSubscription() = 0;

    // Notification that a node was touched.
    // The |location_dips_screen| parameter contains the location where the touch
    // occurred in DIPs in screen coordinates.
    // The |editable| parameter indicates if the node is editable, for e.g.
    // an input field, etc.
    virtual void FocusedNodeTouched(const gfx::Point& location_dips_screen,
        bool editable)
        = 0;

    // Informs the view that its associated render widget has frames to draw and
    // wants to have BeginFrame messages sent to it.  This should only be called
    // when the value has changed.  Views must initially default to false.
    virtual void SetNeedsBeginFrames(bool needs_begin_frames) = 0;

#if defined(OS_MACOSX)
    // Return the accelerated widget which hosts the CALayers that draw the
    // content of the view in GetNativeView. This may be null.
    virtual ui::AcceleratedWidgetMac* GetAcceleratedWidgetMac() const = 0;

    // Set the view's active state (i.e., tint state of controls).
    virtual void SetActive(bool active) = 0;

    // Brings up the dictionary showing a definition for the selected text.
    virtual void ShowDefinitionForSelection() = 0;

    // Returns |true| if Mac OS X text to speech is supported.
    virtual bool SupportsSpeech() const = 0;
    // Tells the view to speak the currently selected text.
    virtual void SpeakSelection() = 0;
    // Returns |true| if text is currently being spoken by Mac OS X.
    virtual bool IsSpeaking() const = 0;
    // Stops speaking, if it is currently in progress.
    virtual void StopSpeaking() = 0;
#endif // defined(OS_MACOSX)
};

} // namespace content

#endif // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_H_
